Pressure indicator



4, 1936. R. G. MINER. JR 2,050,113

PRESSURE INDICATOR 2 Sheets-Sheet 1 Filed NOV. 21, 1931 INVENTOR. ROBERT G. MINER, JR.

fy az's aIZZvr-ne ya Aug. 4, 1936. R. s. MINER. JR

PRESSURE INDICATOR Filed Nov. 21, 1931 2 Sheets-Sheet 2 m a u M w a ki v; jwim 7| II a m wk .2 m E a E 3!; m i R an R w? NR QM INVENTOR ROBERT C. MINER, JR.

Patented Aug. 4, 1936 UNITED STATES PATENT OFFICE PRESSURE INDICATOR Equipment ware (1935) Corporation, a corporation of Dela- Application November 21, 1931, Serial No. 576,566

10 Claims.

This invention relates to pressure indicators and more particularly to pressure indicators which give an indication when a predetermined or critical pressure is reached and it is an object of this invention to provide an improved pressure indicator which will be operated to give an indication when a predetermined pressure is reached. It is also an object of this invention to provide a pressure indicator having pressure responsive means subjected to the pressure whose condition is to be indicated and operated to cause an indication to be given when the pressure to which it is subjected falls to a predetermined pressure.

In the drawings- Fig. 1 is a. diagrammatic view of an apparatus for using gas under pressure with a pressure indicator constructed in accordance with this invention applied thereto Fig. 2 is a view partly in section and partly in elevation of the pressure indicator shown in Fig. 1;

Fig. 3 is a view in section of part 01' the pressure indicator shown in Fig. 2;

Fig. 4 is a vertical section taken on the line 44 of Fig. 3;

Fig. 5 is a view in section of another part of the pressure indicator shown in Fig. 2; and

Fig. 6 is a vertical section taken on the line 68 01' Fig. 5.

In the drawings an apparatus constructed in accordance with this invention is shown applied to an apparatus using the gas from containers containing gas under pressure. As shown, gas storage containers 4 and I having outlet valves 2 and 2' are joined by pipes 3 and 3 to a header 4, valves 5 and 5 being provided for cutting on the connection of either container from the header. From the header the gas passes through a reducing valve 6 and a pipe line I to the means in which it is used, such a means being shown in Fig. 1 as a gas stove 8. For purposes of this kind, tanks l and I are furnished containing gas under considerable pressure and one container, at a time, is connected to the header 4 and thegas supplied by pipe line I to the point of consumption. As the gas is used, the pressure in the connected container as container I falls and in order to notify the consumer that it is neessary to connect a fresh tank to the header as the gas in the tank connected is becoming exhausted, there is provided an indicating mechanism comprising a pressure unit Ill connected through pipe l2 to the header 4 and through a pipe [4 to an indicating means It which is placed where it is observed by the person using the gas supply.

The pressure unit Ill comprises a lower casting l8 and an upper casting 20, the lower casting having a threaded opening 22 by which the casting is attached to the pipe l2 and an annular flange 24 which forms a seat for a diaphragm 2B and is perforated to receive the bolts 28 by means 5 of which the upper casting 20 is secured to the lower casting IS, the upper casting 20 and the bolts 28 serving to retain the diaphragm 26 on its seat. The upper casting 20 comprises a substantially flat or plate portion 2| having a substantially inverted U-shaped housing 30 formed integral therewith. To the upper portion of the housing 30 are secured extensions 32 having outwardly projecting flanges 34 provided with openings and adapted to serve as an attaching bracket for the pressure unit Ill when desired. In the upper portion of the housing 30 is a threaded opening in which is adjustably secured a sleeve 36 having a rod or plunger 38 slidably mounted therein. To the lower end of the plunger 38 is secured an inverted substantially Ushaped yoke 40 which, at its lower end, is pivotally connected to a rod 42 which projects through an opening in the plate portion 2| of the upper casting 20 and is provided with a circular head 44 which bears upon the diaphragm 26. One side 0! the housing 30 is provided with a threaded opening in which is mounted a hollow bushing 46 which serves to secure a cylinder 48 to the housing 30 and as a guide for the rod 50 which is connected, at one end, to a piston 52 in the cylinder 48 and extends through the bushing 46 and through an opening in the opposite side of the housing 30. The rod 50 is provided at its other end with an operating knob or handle 54. Between the piston 52 and the outer end of the cylinder 48 is placed a spring 56 which tends to return piston 52 to the end of the cylinder 48 adjacent the housing 30.

Intermediate its length the rod 50 is formed with a notch 58 which is engaged by a latch 60 formed as a yoke pivoted at 62 to the housing 30 and having a portion 60 adapted to engage in the notch 58. The side portions of the latch 60 pass outside oi the yoke 40 and are positioned to be engaged by projections 40 on the side portions of the yoke 40 when the yoke 40 is moved downwartfiy by a spring 64 which surrounds the plunger 38 and is compressed between the upper portion of the yoke 40 and the inner end of the sleeve 36. To ensure engagement of the latch 60 in the notch 58 when the latch is not pressed downwardly by the yoke 40 there is provided a spring 66 confined between the portion 60' of the latch Gil and the flat portion 2| 0! the upper casting 20. Detachable sides 51 are secured to the hous- 55 ing 88 by bolts 59 to complete the enclosing of the apparatus.

Extending from the cylinder 48 is a tube I4 of extremely small bore so that the volume thereof will be relatively small compared to the volume of the cylinder 48. The tube l4 extends to an indicating means I8 comprising a base plate I8 to which is secured a cylinder I2 connected to the tube I4 and having a piston I4 loosely fitted therein. The piston I4 is connected through connecting rod I8 to one end of counter-weighted arm I8 plvotally mounted on pin 88 supported by the base plate 18. Projecting from the arm I8 is a weighted angularly disposed arm 82 which engages with the stops 83 and 83' to limit the movement of the arm I8 and the arm I8 is also provided with a projection 84 which is concentric with the pivotal axis of the arm I8 and carries an indicating dial 88. To the baseplate I8 is secured an annular side wall 88 to which is attached a perforated front plate 98 and a glass cover 82.

If it is desired to give an additional indication at some point remote from the indicating means I8 there may be provided an audible indicating means as a bell 94 operated by current supplied from a battery 98 or other suitable source of current through a circuit comprising leads 91 and 88 which extend to contacts 99 and I88 carried by the baseplate 18. As shown in Figure 6, contact I88 is provided with an extension adapted in one position of the arm I8 to be engaged by insulated pin 82' mounted on the arm 82 to cause the contacts 89 and I88 to engage, completing the circuit for the bell 94. An additional audible indication may be given as by bell 8i supplied with current from a suitable source of current, as battery 88, by a circuit comprising leads I8l and I82 which extend to contacts I83 and I84 carried by the housing 38. Contact I83 is extended so as to be engaged by insulated pin I88 carried by the yoke 48 and positioned to separate the contacts I88 and I84 when the yoke 48 is in its upper position.

With the pressure unit I8 connected to the header 4, and gas being supplied thereto from one of the tanks the pressure in the header 4, passing through pipe l2 and acting upon the diaphragm 28 is normally suflicient to overcome the resistance of the spring 84 and raise the plunger 42, yoke 48 and plunger 88 to their uppermost position as shown in Figure 3. With the yoke 48 raised, movement of the rod 88 by handle 84 to the left as shown in Figure 3, will permit the spring 88 to raise the latch 88 so that the part 88' thereof engages in the'notch 88 in the rod 88, thus retaining the piston 82 in the position shown in Figure 3 with the spring 88 under compression. When thus raised the yoke 48 through the engagement of the pin I88 with the contact I88, raises the contact I88 and interrupts the circuit between the contacts I88 and I84 and prevents any signal being given by means of the bell 8|. Movement of the rod 88 and piston 82 to the left in Figure 3 causes pressure to be generated in cylinder 48 and tube I4 which acts upon the piston I4, raising piston 14 and shifting arm I8 and arm 82 to the dotted line position shown in Figure 6 and rotating the dial 88 therewith so that the dial 88 gives an indication that the pressure in the header 4 is above that at which the pressure unit I8 operates. Movement of the arm I8 and the arm 82 carries the pin 82' away from the contact I88, permitting the contacts 88 and I88 to separate and open the circuit of the hell 4,

thus preventing any indication being given by 4 is consumed, the pressure in the tank falls untileventually a pressure is reached at which the spring 84 overcomes the pressure acting upon diaphragm 28 and through yoke 48 and plunger 42 forces diaphragm 28 downwardly. The yoke 48, through its projections 48', operates the yoke 88 and disengages the portion 88' thereof from the notch 88 of the rod 88 permitting the spring 88 to force the piston 82 to the other end of the cylinder 48. The movement of the piston 82 reduces the pressure in the pipe I4 and causes a difference of pressure at opposite sides of the piston I4 which operates the piston I4, moving the arm 18 to the position shown'in full lines in Figure 6 and shifting the dial 88 to give an indication that the pressure in the tank has fallen to the point at which it is desirable to substitute another tank. The pressure at which spring 84 operates the diaphragm 28 is determined by the adjustment of the sleeve 88.

When an audible indication is connected with the indicating unit I8, the movement of the arm I8 and arm 82 causes the pin 82' to engage the contact I88, moving contact I88 to engage with contact 98 and complete the circuit of the bell 84 to give an audible indication of the pressure in the tank.

Where an audible indication is given by the pressure unit I8 the movement of the yoke 48 withdraws the pin I88 from the contact I88 permitting the contact I88 to engage with the contact I84 and complete the circuit for the audible signal 8|.

When the depleted tank has been disconnected and a charged tank connected to the header 4, the increased pressure in the header 4 acting upon the diaphragm 28 overcomes the resistance of spring 84, raising the yoke 48 and permitting the latch 88 to be raised by the spring 88. The operator may then restore the piston 82 to the position shown in Figure 3, whereupon the latch 88 will engage in the notch 88 and retain the piston in that position. This movement of the piston resets the indicator I8 to the normal indication and shifts the arm 82 and pin 82' to disengage the pin 82' from the contact I88 and open the circuit of the bell 84. The raising of the diaphragm 28 and the yoke 48 causes the pin I88 to disengage the contact I83 from the contact I84 and opens the circuit of the bell 8|.

What is claimed is:-

l. A pressure indicator comprising an indicating means, means for operating said indicating means including pressure operated means, means comprising a spring actuated piston for developing fluid pressure for operating said pressure operated means, means for shifting said piston to compress said spring, means retaining said piston in position with the spring compressed and means responsive to the pressure whose condition is to be indicated for releasing said spring actuated piston.

2. A pressure indicator comprising an indicating means, pressure operated means, means connecting said pressure operated means and said indicating means, means comprising a spring operated plunger for developing fluid pressure for operating said pressure operated means, a latch for preventing operation of said plunger by said spring to develop fluid pressure to operate said pressure operated means and means responsive to the pressure whose condition is to be indicated for operating said latch.

3. A pressure indicator comprising an indicating means, pressure operated means. means connecting said pressure operated means and said indicating means, means comprising a spring operated plunger for developing fluid pressure for operating said pressure operated means, a latch for preventing operation of said plunger by said spring to develop fluid pressure to operate said pressure operated means and means operative upon the fall to a predetermined degree of the pressure whose condition is to be indicated to release said plunger from said latch;

4. A pressure indicator comprising an indicating means, means comprising pressure operated reciprocating means, means connecting said reciprocating means and said indicating means, means comprising a piston for varying the pressure to operate said pressure operated means, means for operating said piston, said operating means comprising a spring biasing the piston to one position, a latch for retaining said piston in position against the action of said spring means for operating said latch to release said piston and means responsive to the pressure whose condition is to be indicated opposing operation of said latch.

5. A pressure indicator comprising an indicating means, pressure operated means, means connecting said pressure operated means and said indicating means, a cylinder in which said pressure operated means is loosely fitted, means comprising a piston for varying the pressure in said cylinder for operating said pressure operated means, said means comprising a spring biasing the piston to one position, means for operating said piston, a latch for retaining said piston in position against the action of said spring, a spring for operating said latch to release said piston and a diaphragm responsive to the pressure whose conditions is to be indicated opposing operation of said latch.

6. In a pressure indicating apparatus, an indicating means, pressure operated means including a piston, means connecting said piston and said indicating means, means comprising a spring operated piston for effecting pressure changes to operate the piston of said pressure operated means in combination with a manually operated means for positioning said piston with the spring compressed, latching means for said manually operated means in its spring compressing position and means for releasing said manually operated means from said latching means operable upon a reduction to a predetermined pressure of the pressure whose condition is to be indicated.

7. In a pressure indicating apparatus, an indicating means, pressure operated means including a piston, means connecting said piston and said indicating means, pressure varying means comprising a spring operated piston for varying the pressure to operate the piston of said pressure operated means in combination with a manually operated mechanism for positioning said piston with the spring compressed, a latch for retaining said manually operated mechanism in spring compressing position, a spring for releasing said latch and pressure responsive means opposing operation of said latch by said spring.

8. In a pressure indicating apparatus, an indicator, pressure responsive means for operating said indicator, means including a spring actuated piston for effecting pressure changes to operate said pressure responsive means, in combination with' manually operable means for setting said piston in opposition to said spring, a latch for holding said piston in a position with said spring compressed, and trip means for releasing said piston upon a predetermined reduction oi the pressure whose condition is to be indicated.

9. In a pressure indicating apparatus, an indicator, pressure responsive means for actuating said indicator, means including a spring biased piston for eifecting pressure changes to operate said pressure responsive means, in combination with manual mechanism for setting said piston in a position with said spring compressed, a latch for said manually operated mechanism, a spring release for said latch, and means responsive to the pressure whose condition is to be indicated for opposing movement of said latch by said spring.

10. Pressure indicating apparatus comprising in combination, an indicator, interconnected cylinders each having a piston therein, resilient means tending to advance one of said pistons, manual means for moving said piston in opposition to said resilient means, a latch for holding said. piston in position in opposition to said resilient means, tripping means for said latch responsive to changes in the pressure to be indicated, and means connecting said indicator and the other of said pistons, the latter being movable in response to fluid pressure changes caused by movement of said first named piston.

ROBERT G. liflNER, JR.

CERTIFICATE or CORRECTION.

Patent No. 2,050, 113. August 4, 1936.

ROBERT G. MINER, JR.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 3, first column, lines 36-57, claim 5, strike out the words and comma "said means comprising a spring biasing the, piston to one position," and insert the same after "piston," in line 38, same claim; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 29th day of September, A. D. 1936.

Henry Van Aradala (Seal) Acting Commissioner of Patents. 

